The present invention generally relates to devices for driving parts, and more particularly relates to devices for automatically delivering fasteners, one-at-a-time, to the nosepiece of a driving device and automatically engaging each fastener to a work piece.
Systems for orienting fasteners, such as screws, bolts, nuts or rivets, from a bulk form into an arrangement whereby the fasteners are aligned and individually transported to an automatic driving device are well known. Generally, such systems include a feeder device which draws fasteners-from a reservoir of disoriented fasteners disposed within a hopper and orients the fasteners to a pre-determined orientation. Such feeder devices may include vibratory parts feeder machinery, an example of which is disclosed in U.S. Pat. No. 5,630,497 to Graham. The oriented parts are transported, one at a time, to an automatic driving device where each fastener is driven into engagement with a work piece. The primary purpose of such systems is to automate production and/or reduce cycle times.
Generally, the fasteners are supplied to the driving device through a flexible delivery tube. The flexible tube supplies individual fasteners to a parts discharge passage defined axially through the nosepiece of the driving device. Typically, the flexible tube is placed in communication with an intermediate feed passage formed integral with the nosepiece and intersecting the discharge passage in an inclined manner. Since the walls of the integrally formed feed passage do not extend into the drive passage, the fasteners have a tendency to tumble and become cocked or jammed within the nosepiece at the angular transition between the feed passage and the discharge passage. Because of this tendency for the fasteners to tumble, the use of prior devices has typically been limited to fasteners having overall lengths significantly greater than their overall widths. Specifically, fasteners having a relatively large length-to-width aspect ratio are less likely to tumble and become jammed in the nosepiece of the device. With prior devices, a minimum aspect ratio greater than 1.5:1 is typically required to reduce the likelihood of jamming.
Since increasing the speed of production is one of the main objectives of an automatic driving device, jamming or malfunctioning of the device is a major drawback. Such jams or malfunctions usually result in a work stoppage, potentially causing a complete shutdown of production or, at a minimum, a slowdown in production. In the event that a fastener should become cocked or jammed, the nosepiece of the device should preferably have the ability to be quickly cleared to regain use of the device and minimize downtime. In some cases, the nosepiece of prior driving devices must be completely disassembled to clear a jammed fastener, thus resulting in a potentially lengthy shutdown of production.
Additionally, existing driving devices are unnecessarily complicated, typically having a relatively large number of intricate parts that are prone to jamming. Existing driving devices are also difficult to clear in the event of jamming and are difficult to disassemble for servicing. Hence, there has been a need for a parts feeding and driving device which addresses some or all of the drawbacks discussed above with regard to prior devices. An effective means for satisfying this need has escaped those skilled in the art. The present invention satisfies this need in a novel and unobvious way.
In one form of the present invention, a device is provided for driving a part, generally comprising a parts driver, a parts receiver and a parts delivery conduit. The parts receiver includes a plurality of retaining elements defining a first passage therebetween and being transitionable between a first configuration to retain the part within the first passage and a second configuration to allow the part to be discharged therefrom. The parts receiver also defines a second passage extending transversely therethrough and intersecting the first passage. The parts delivery conduit is at least partially disposed within the second passage and includes an end portion extending into the first passage to guide the part into the first passage.
In another form of the present invention, a device is provided for driving a part, generally comprising a parts driver, a nosepiece and a parts delivery conduit. The nosepiece includes at least three jaws defining an axial passage therebetween and being transitionable between a first configuration to retain the part within the axial passage and a second configuration to allow the part to be discharged therefrom. An adjacent pair of the jaws defines a transverse passage intersecting the axial passage. The parts delivery conduit is positioned in communication with the transverse passage to deliver the part through the transverse passage and into the axial passage.
In a further form of the present invention, a device is provided for driving a part, generally comprising a parts driver, a parts receiver and a parts delivery conduit. The parts receiver defines an axial passage and a transverse passage intersecting the drive passage. The parts delivery conduit includes a movable portion and a stationary portion. The movable portion is displaceable between a first position in which the movable portion is positioned in communication with the transverse passage to deliver the part through the transverse passage and into the axial passage and a second position in which the movable portion is displaced in an outward, transverse direction. The stationary portion is disposed proximately adjacent the movable portion to define a substantially continuous parts delivery flowpath when the movable portion is in the first position.
In yet another form of the present invention, a device is provided for driving a part into engagement with a work piece. The device comprises means for receiving the part, including at least three jaws defining an axial parts drive passage, with an adjacent pair of the jaws defining a parts inlet passage therebetween in communication with the drive passage. The device further comprises means for biasing the jaws toward one another to enable the jaws to selectively retain the part within the drive passage in a drive position, and means for delivering the part through the inlet passage and into the drive passage. The delivering means includes means for guiding the-part into the drive passage, with the guiding means being pivotable between a first position in which an end portion of the guiding means is at least partially disposed within the drive passage and a second position in which the end portion is pivoted in an outward direction transverse to the drive axis. The device additionally comprises means for driving the part from the drive passage and into engagement with the work piece.
In still another form of the present invention, a method is provided for driving a part having a head and an internally threaded shank into engagement within an opening in a work piece. The method comprises: a.) providing a parts driver having a drive shaft extending along a drive axis and defining a threaded portion engageable with the internally threaded shank, with the parts: driver being adapted to displace the drive shaft generally along the drive axis and to rotate the drive shaft about the drive axis, and a receiver defining an axial passage extending generally along the drive axis and opening onto a distal end of the receiver; b.) delivering a part into the axial passage with the shank extending toward the distal end of the receiver; c.) engaging the drive shaft to the part; d.) discharging the part from the axial passage and positioning the head of the part beyond the distal end of the receiver by displacing the drive shaft in a first axial direction; e.) compressing the head of the part against the distal end of the receiver by displacing the drive shaft in a second axial direction generally opposite the first axial direction to substantially prevent rotation of the part about the drive axis relative to the receiver; f.) positioning the shank of the part within the opening in the work piece; and g.) threading the threaded portion of the drive shaft along the internally threaded shank by rotating the drive shaft about the drive axis in a first rotational direction, the threading causing a portion of the shank to buckle, the work piece being securely engaged between the head and the buckled portion of the shank.
One object of the present invention is to provide a unique device and method for driving a part.
Related objects and advantages of the present invention will become apparent from the following illustrations and description.